AI 中文总结
本研究提出动力学摩擦是MiSaTaQuWa引力自作用力方程协变多参数展开中的环境相关项，而非独立耗散机制，经弱场绝热极限验证重现经典阻力结果，还预言强场新特征，拓展了自作用力理论适用范围，对LISA极端质量比旋近波形建模有重要价值。
AI 中文摘要
动力学摩擦（DF）和引力波辐射反作用通常被视为作用于在物质环境中旋近的致密天体的两种不同耗散机制。我们证明，动力学摩擦并非一种额外的力，而是MiSaTaQuWa力方程协变多参数展开中$q^2ε$阶的一项，其中$q$为质量比，$ε$为环境参数；当不存在粒子引发的环境物质场扰动时，该项恒为零。作为对这一界定的检验，我们在弱场绝热极限下对其进行计算，求解由粒子自身$q$阶真空度规扰动所源生的极向密度扰动方程。该约化结果重现了Chandrasekhar-Ostriker阻力，并预言了强引力场中的两个特征：一是尾迹的依赖于$\boldsymbol{\u2113}$的分裂（仅在弱场极限下才会重新组合为Ostriker源；二是不存在牛顿对应项的纯相对论性轴向贡献。这一研究确立了动力学摩擦是自作用力理论的固有组成部分，可推广至强场、一般轨道和一般环境，对LISA的极端质量比旋近波形建模具有直接意义。
英文摘要
Dynamical friction (DF) and gravitational-wave radiation reaction are conventionally treated as distinct dissipative mechanisms acting on a compact object inspiraling through a matter environment. We show that DF is not an additional force but a term at order $q^2ε$ in a covariant multiparameter expansion of the MiSaTaQuWa force equation that vanishes identically in the absence of a particle-induced perturbation of the environment's matter fields, where $q$ and $ε$ are respectively the mass ratio and environmental parameter. As a test of this identification, we evaluate it in weak and adiabatic field limit, solving the polar density-perturbation equation sourced by the particle's own order-$q$ vacuum metric perturbation. The reduction reproduces the Chandrasekhar-Ostriker drag force and predicts two features in strong gravity. An $\ell$-dependent splitting of the wake that only recombines into the Ostriker source in the weak-field limit, and a purely relativistic axial contribution with no Newtonian counterpart. This establishes dynamical friction as an intrinsic piece of self-force theory, extending to strong field, generic orbits, and generic environments, with direct consequences for extreme-mass-ratio inspiral waveform modeling for LISA.
